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There is great concern in equine sport over the potential use of pharmaceutical agents capable of editing the genome or modifying the expression of gene products. Synthetic oligonucleotides are short, single-stranded polynucleotides that represent a class of agents capable of modifying gene expression products with a high potential for abuse in horseracing. As these substances are not covered by most routine anti-doping analytical approaches, they represent an entire class of compounds that are not readily detectable. The nucleotide sequence for each oligonucleotide is highly specific, which makes targeted analysis for these agents problematic. Accordingly, we have developed a non-targeted approach to detect the presence of specific product ions that are not naturally present in ribonucleic acids. Briefly, serum samples were extracted using solid-phase extraction with a mixed-mode cartridge following the disruption of protein interactions to isolate the oligonucleotides. Following the elution and concentration steps, chromatographic separation was achieved utilizing reversed-phase liquid chromatography. Following an introduction to a Thermo Q Exactive HF mass spectrometer using electrospray ionization, analytes were detected utilizing a combination of full-scan, parallel reaction monitoring and all ion fragmentation scan modes. The limits of detection were determined along with the accuracy, precision, stability, recovery, and matrix effects using a representative 13mer oligonucleotide. Following method optimization using the 13mer oligonucleotide, the method was applied to successfully detect the presence of specific product ions in three unique oligonucleotide sequences targeting equine-specific transcripts.

Monofluoroacetate is a highly lethal toxin that causes death by inhibiting cellular adenosine triphosphate (ATP) production. The heart and brain are the primary target organs. Acute death is attributed to cardiac fibrillation and/or convulsions. Although it occurs naturally in some plants, a major source of animal intoxication is access to sodium monofluoroacetate (NaMFA) pesticide, which continues to be a concern in the USA and around the world despite restricted use in some countries including the USA. There are also concerns about misuse of this pesticide for malicious poisoning. Currently, a tissue-based diagnostic method for NaMFA intoxication in animals is lacking. There is a critical need by the veterinary diagnostic community for a simple, sensitive and reliable tissue-based diagnostic test to confirm NaMFA poisoning in animals. We have developed and extensively evaluated a sensitive novel liquid chromatography combined with tandem mass spectrometry method suitable for this purpose. The limits of detection and limits of quantitation are 1.7 and 5.0 ng/g, respectively. The accuracy and precision met or exceeded expectations. The method performance was verified using the incurred kidney obtained from animal diagnostic cases. This novel kidney-based method is now available for clinical use and can help with diagnostic purposes, including detecting potential issues related to animal foods.

Sphingolipids are an essential subset of bioactive lipids found in most eukaryotic cells that contribute to membrane biophysical properties and are involved in cellular differentiation, recognition, and mediating interactions. The described nanoHPLC-ESI-Q/ToF methodology utilizes known biosynthetic pathways, accurate mass detection, optimized collision-induced disassociation, and a robust nanoflow chromatographic separation for the analysis of intact sphingolipids found in human tissue, cells, and serum. The methodology was developed and validated with an emphasis on addressing the common issues experienced in profiling these amphipathic lipids, which are part of the glycocalyx and lipidome. The high sensitivity obtained using nanorange flow rates with robust chromatographic reproducibility over a wide range of concentrations and injection volumes results in confident identifications for profiling these low-abundant biomolecules.

Short-chain fatty acids (SCFAs) comprise the largest group of gut microbial fermentation products. While absorption of most nutrients occurs in the small intestine, indigestible dietary components, such as fiber, reach the colon and are processed by the gut microbiome to produce a wide array of metabolites that influence host physiology. Numerous studies have implicated SCFAs as key modulators of host health, such as in regulating irritable bowel syndrome (IBS). However, robust methods are still required for their detection and quantitation to meet the demands of biological studies probing the complex interplay of the gut-host-health paradigm. In this study, a sensitive, rapid-throughput, and readily expandible UHPLC-QqQ-MS platform using 2-PA derivatization was developed for the quantitation of gut-microbially derived SCFAs, related metabolites, and isotopically labeled homologues. The utility of this platform was then demonstrated by investigating the production of SCFAs in cecal contents from mice feeding studies, human fecal bioreactors, and fecal/bacterial fermentations of isotopically labeled dietary carbohydrates. Overall, the workflow proposed in this study serves as an invaluable tool for the rapidly expanding gut-microbiome and precision nutrition research field.

INTRODUCTION: While known animal exposures to human drugs of abuse (DA) were previously considered relatively uncommon in veterinary medicine, the trends are changing. Marijuana and amphetamines are among the 20 toxicants most frequently consulted about with the Pet Poison Helpline. When such exposures occur, they are typically considered emergencies. METHODS: This retrospective study describes confirmed cases of DA exposure in pets from the California Animal Health and Food Safety Laboratory System (CAHFS), 2013-2023. RESULTS: Fifty-seven samples tested positive for DA through liquid chromatography with tandem mass spectrometry analysis (qualitative method). In 75% (43/57) of the DA screen tests, the detected drugs included amphetamine-type stimulants and metabolites (methamphetamine, amphetamine, or both). In 47% (27/57) of cases, a combination of more than one drug group was found. Most cases were diagnosed from a urine specimen. In at least 32% (18/57) of cases, the samples were submitted due to suspicions of animal cruelty, and at least 41% (23/57) of the patients were deceased when the samples were submitted. DISCUSSION: More studies on the prevalence of illicit drugs in small animals, using confirmatory testing, are warranted to fully understand the significance of this emerging toxicological hazard in veterinary medicine.

Microbial competition within plant tissues affects invading pathogens' fitness. Metabolomics is a great tool for studying their biochemical interactions by identifying accumulated metabolites. Xylella fastidiosa, a Gram-negative bacterium causing Pierce's disease (PD) in grapevines, secretes various virulence factors including cell wall-degrading enzymes, adhesion proteins, and quorum-sensing molecules. These factors, along with outer membrane vesicles, contribute to its pathogenicity. Previous studies demonstrated that co-inoculating X. fastidiosa with the Paraburkholderia phytofirmans strain PsJN suppressed PD symptoms. Here, we further investigated the interaction between the phytopathogen and the endophyte by analyzing the exometabolome of wild-type X. fastidiosa and a diffusible signaling factor (DSF) mutant lacking quorum sensing, cultivated with 20% P. phytofirmans spent media. Liquid chromatography-mass spectrometry (LC-MS) and the Method for Metabolite Annotation and Gene Integration (MAGI) were used to detect and map metabolites to genomes, revealing a total of 121 metabolites, of which 25 were further investigated. These metabolites potentially relate to host adaptation, virulence, and pathogenicity. Notably, this study presents the first comprehensive profile of X. fastidiosa in the presence of a P. phytofirmans spent media. The results highlight that P. phytofirmans and the absence of functional quorum sensing affect the ratios of glutamine to glutamate (Gln:Glu) in X. fastidiosa. Additionally, two compounds with plant metabolism and growth properties, 2-aminoisobutyric acid and gibberellic acid, were downregulated when X. fastidiosa interacted with P. phytofirmans. These findings suggest that P. phytofirmans-mediated disease suppression involves modulation of the exometabolome of X. fastidiosa, impacting plant immunity.

The computation of entropy in liquids and liquid crystal (LC) phases is a big challenge in statistical physics. In this work, we extend the two-phase thermodynamic model (2PT) to shape anisotropic soft repulsive spherocylinders (SRSs) and report the absolute values of entropy for different LC phases for a range of aspect ratios L/D = 2 − 5. We calculate the density of states for different LC phases and decompose it into contributions arising from translational and rotational degrees of freedom. The translational and rotational modes are further partitioned into diffusive, gas-like, and non-diffusive, solid-like components using a fluidicity factor. In the dilute limit, the entropy values obtained from the 2PT method match exactly those of an ideal rigid rotor. We find that, for a given packing fraction, the magnitude of the total entropy is roughly equal regardless of the different LC phases associated with different aspect ratios. We also compute the excess entropy (for L/D = 5) and compare those with the values obtained using the standard integration approach of MD or Monte Carlo equation of state of SRS. The values obtained using both approaches match very well. The rotational and translational fluidicity factors are further used to determine the phase boundaries of different LC phases. [ABSTRACT FROM AUTHOR]

The widespread application of enzymes in industrial chemical synthesis requires efficient process control to maintain high yields and purity. Flow injection analysis-electrospray ionization-mass spectrometry (FIA-ESI–MS) offers a promising solution for real-time monitoring of these enzymatic processes, particularly when handling challenging compounds like sugars and glycans, which are difficult to quickly analyze using liquid chromatography-mass spectrometry due to their physical properties or the requirement for a derivatization step beforehand. This study compares the performance of FIA-MS with traditional hydrophilic interaction liquid chromatography (HILIC)-ultra high-performance liquid chromatography (UHPLC)-mass spectrometry (MS) setups for the monitoring of the enzymatic synthesis of N-acetyllactosamine (LacNAc) using beta-1,4-galactosyltransferase. Our results show that FIA-MS, without prior chromatographic separation or derivatization, can quickly generate accurate mass spectrometric data within minutes, contrasting with the lengthy separations required by LC–MS methods. The rapid data acquisition of FIA-MS enables effective real-time monitoring and adjustment of the enzymatic reactions. Furthermore, by eliminating the derivatization step, this method offers the possibility of being directly coupled to a continuously operated reactor, thus providing a rapid on-line methodology for glycan synthesis as well. [ABSTRACT FROM AUTHOR]

Accurate measurement of serum glycocholic acid (GCA) is crucial for evaluating the activity of chronic hepatitis. Moreover, GCA is a novel identified biomarker for hepatocellular carcinoma. Although some laboratories have used the liquid chromatography-tandem mass spectrometry (LC–MS/MS) method to measure GCA in recent years, the problem of potential interference of GCA analogues has not been solved well yet. Neither reference measurement procedures nor reference materials for GCA have been listed in the Joint Committee for Traceability in Laboratory Medicine (JCTLM) database. For standardization of GCA, it is urgent to establish a candidate measurement procedure for GCA. In this study, a candidate reference measurement procedure for the quantification of GCA in human serum based on isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC–MS/MS) by a two-step sample pretreatment of protein precipitation and MAX solid-phase extraction was developed and validated. GCA can be completely separated from its structural analogues with gradient elution in 9 min compared with short time gradients published in previous literature by Huang's group. Method validation indicated perfect quantitation precision with intra-day and inter-day values that were ≤1.30% and ≤1.80%, respectively. The method showed excellent linearity with high regression coefficients (R2 > 0.999) over a range of 0.92 ng/g–38.38 μg/g and perfect recoveries at three spiked levels (99.87–100.43%). No interference, matrix effect, and carryover were observed. Moreover, the cRMP was successfully applied to measure GCA in serum samples and compared with two immunoassays in a clinical laboratory. As a candidate reference method, this method can promote a GCA standardization program. [ABSTRACT FROM AUTHOR]

Accurate diagnostic and serology assays are required for the continued management of the COVID-19 pandemic yet spike protein mutations and intellectual property concerns with antigens and antibodies used in various test kits render comparability assessments difficult. As the use of common, well-characterized reagents can help address this lack of standardization, the National Research Council Canada has produced two protein reference materials (RMs) for use in SARS-CoV-2 serology assays: biotinylated human angiotensin-converting enzyme 2 RM, ACE2-1, and SARS-CoV-2 Omicron BA.4/5 spike protein RM, OMIC-1. Reference values were assigned through a combination of amino acid analysis via isotope dilution liquid chromatography tandem mass spectrometry following acid hydrolysis, and ultraviolet–visible (UV–Vis) spectrophotometry at 280 nm. Vial-to-vial homogeneity was established using UV–Vis measurements, and protein oligomeric status, monitored by size exclusion liquid chromatography (LC-SEC), was used to evaluate transportation, storage, and freeze–thaw stabilities. The molar protein concentration in ACE2-1 was 25.3 ± 1.7 µmol L−1 (k = 2, 95% CI) and consisted almost exclusively (98%) of monomeric ACE2, while OMIC-1 contained 5.4 ± 0.5 µmol L−1 (k = 2) spike protein in a mostly (82%) trimeric form. Glycoprotein molar mass determination by LC-SEC with multi-angle light scattering detection facilitated calculation of corresponding mass concentrations. To confirm protein functionality, the binding of OMIC-1 to immobilized ACE2-1 was investigated with surface plasmon resonance and the resulting dissociation constant, KD ~ 4.4 nM, was consistent with literature values. [ABSTRACT FROM AUTHOR]

Rationale: To uphold the integrity of horseracing and equestrian sports, it is critical for an equine doping control laboratory to develop a comprehensive screening method to cover a wide range of target substances at the required detection levels in equine urine. Methods: The procedure involved the enzymatic hydrolysis of 3 mL urine samples followed by solid‐phase extraction using HF Bond Elut C18 cartridge. The resulting extracts were then separated on a C18 reversed‐phase column and analyzed using liquid chromatography/high‐resolution mass spectrometry (LC/HRMS) in both electrospray ionization positive and negative modes in two separate injections. The analytical data were obtained in full scan and product ion scan (PIS) modes in an 11 min LC run. Results: The method can detect 1011 compounds (in both positive and negative ion modes). Over 95% of the target compounds have limits of detections (LODs) ≤10 ng/mL, and more than 50% of the LODs are ≤0.5 ng/mL. The lowest LOD can reach down to 0.01 ng/mL. The applicability of the method was demonstrated by the successful detection of prohibited substances in overseas and domestic equine urine samples. Conclusions: We have successfully developed a regular screening method for equine urine samples that can detect more than 1000 compounds at sub‐ppb levels in both positive and negative ion modes with full scan and PIS using LC/HRMS. Furthermore, this method can theoretically be expanded to accommodate an unlimited number of prohibited substances in full‐scan mode. [ABSTRACT FROM AUTHOR]

Rationale: Rivaroxaban is an anticoagulant prescribed to patients who are at risk of medical conditions such as deep‐vein thrombosis, pulmonary embolisms, and strokes caused by blood clots. The administration of this drug is monitored to adjust the dosage and evaluate patients' blood concentration. Rapid quantification of this drug in plasma could make it possible to ensure that the dose present in the blood of patients does not represent a danger for the medical intervention to be carried out. Methods: Liquid chromatography–tandem mass spectrometry is usually employed to quantify rivaroxaban in blood, plasma, and serum. Here, an alternative method of analysis based on laser diode thermal desorption–triple quadrupole mass spectrometry (LDTD‐QqQMS) was developed and comprehensively validated. This new method allows the quantification of rivaroxaban in less than 13 s from sample to sample. The extraction of rivaroxaban in human serum was done by a salting‐out liquid–liquid extraction with acetonitrile and a saturated sodium chloride solution. Results: The proposed method allows the quantification of rivaroxaban in less than 13 s from sample to sample. During validation, all criteria were respected. The accuracy was <15% of the nominal value, the precision was <15%CV, and the recovery was ≥89.9%. There were no observed carryover or matrix effects. Analysis of the extracted samples established the stability of dry (24 h) and wet samples (1 week) when samples cannot be analyzed immediately, a considerable advantage in a clinical setting. Conclusions: This method improves sample throughput by more than 1200% compared to liquid chromatography–tandem mass spectrometry methods of analysis of rivaroxaban and decreases analysis costs by reducing solvent consumption and instrument time. [ABSTRACT FROM AUTHOR]

This article presents a study on the use of urinary guanidino compounds (GCs) and ureido compounds (UCs) as biomarkers for cardiac surgery-associated acute kidney injury (CSA-AKI). The study utilized a benzylic rearrangement reaction and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze the concentrations of GCs/UCs in urine samples from patients with CSA-AKI at different stages. The findings suggest that certain GC/UC metabolites show significant changes in concentration during CSA-AKI and could potentially serve as biomarkers for different stages of AKI. This research provides valuable resources and new therapeutic targets for further study on CSA-AKI. [Extracted from the article]

Rationale: Lomerizine (LMZ) is an antimigraine drug that works as a calcium channel blocker and has selective effects on the central nervous system. It is metabolized into trimetazidine (TMZ), which is a prohibited substance owing to its performance‐enhancing effects in both human and animal sports. Effective doping control measures are imperative to distinguish the source of TMZ in samples to ensure integrity and fairness of the sport, therefore a comprehensive analysis of LMZ metabolites is essential to identify potential biomarkers in camel urine for effective doping control. Methods: Camel urine samples were collected from four healthy animals following a single oral administration of LMZ at a dosage of 1 mg/kg body weight. In vitro studies were conducted using homogenized camel liver samples. Lomerizine and its metabolites were extracted using solid‐phase extraction and analyzed with a Thermo Fisher Orbitrap Exploris liquid chromatography mass spectrometry system. The acquired data was processed with the Compound Discoverer software. Results: The study conducted a comprehensive analysis of LMZ metabolites in camels and identified 10 phase I and one phase II metabolites. The primary pathway for the formation of phase I metabolites was de‐alkylation, while phase II metabolite was formed through alkylation of the parent drug. The study provided valuable insights into the unique metabolic pathways of LMZ in camels under specific experimental conditions. Conclusion: The developed method enables the detection and characterization of LMZ and its metabolites in camels. The identified metabolites has the potential to act as marker metabolites for the distinctive detection of LMZ in camel urine to ensure efficient analytical strategies for routine doping control applications. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the plasma (PL) and seminal plasma (SP) pharmacokinetic profile of ceftiofur (CEFT) and desuroylceftiofur acetamide (DFCA) after administration of CEFT crystalline-free acid (CCFA) by SC route in two sites of the ear in beef bulls. Four clinically healthy Hereford bulls received a comprehensive physical exam and subsequently a breeding-soundness examination, CBC, and chemistry profile panel. All bulls were diagnosed healthy and satisfactory potential breeders. In one group (n = 2), a single dose of CCFA was administered SC route at the base of the ear (BOE) at a dose of 6.6 mg/kg of body weight. The second group (n = 2) was also administered by SC route in the middle third of the posterior aspect of the ear (MTE). The concentrations of CEFT and DFCA in PL and SP were determined by a high-performance liquid chromatography mass spectrometry (HPLC-MS). Blood and semen samples were collected before the administration of CCFA and at 12, 24, 36, 48, 72, 96, 120, 144, and 168 h after injection. No levels of CEFT were detected in PL and only in 20 of the 40 SP samples (P = 0.0001). The mean level of CEFT in SP was 0.11 % in comparison with the DFCA level. DFCA was found in all PL and SP samples. Therefore, DFCA was chosen to be utilized in the study of the pharmacokinetics parameters both in PL and SP. There were no differences in the mean PL levels of DFCA for the two sites of SC administration between the BOE (102.9 ± 78.9 ng/mL; X ± SD) and to MTE (116.1 ± 70.2 ng/mL; P = 0.58). The mean SP levels of DFCA after administration in the BOE was 857 ± 747 ng/mL, and for the MTE was 549 ± 488 ng/mL without differences between both sites (P = 0.15). The mean level of DFCA in PL was 109.5 ± 74.0 ng/mL, which was lower than the mean SP levels of 695 ± 103 ng/mL (P = 0.001). Moreover, the PL peak DFCA concentration (C max) was 229 ± 46 ng/mL at 36.0 ± 29.4 h (T max) post-administration. The SP C max was 1851 ± 533 ng/mL at 30.0 ± 28.6 h (T max) post-administration. The C max between PL and SP were distinctive (P = 0.004) without any differences in T max between PL and SP (P = 0.60). The terminal half-life for PL DFCA (47.4 ± 29.3 h) was not different than in SP (53.1 ± 23.6 h; P = 0.77). The PL area under the curve concentration time from the first to the last sample (AUC 0–last) was 18,984 ± 4841 ng/mL/h, which was significatively smaller compared with 125,677 ± 59,445 ng/mL/h for SP AUC 0–last (P = 0.04). The PL mean residence time from the first to the last sample (MRT 0–last) was 69.7 ± 15.1 h, and it was similar than for SP of 66.5 ± 7.7 h (P = 0.69). From the present investigation, based in its pharmacokinetic features, it was concluded that CCFA should be an appropriate antibiotic that could be used for the treatment of bull genital infections when its indication is properly outlined. To study the pharmacokinetics of CCFA in SP, DFCA metabolite was appropriated. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) in the air are one of the major concerns due to their possible health risks. In addition, airborne microplastics act as a carrier for several toxic air pollutants and cause carcinogenic, mutagenic and teratogenic effects. Nylon 66 is one of the most abundant MPs in the microenvironments. In this study, we report an optimized method for the quantification of nylon 66 MPs present in the fine particulate matter (PM2.5) using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). The optimized method exhibited excellent linearity, recovery rates, intraday and interday precision and sensitivity. The optimized method was deployed to carry out a pilot study to measure the mass concentrations of nylon 66 microplastics present in the inhalable fraction of particulate matter collected in a shopping complex. The observed mass concentrations of nylon 66 MPs in this study are in the range from 0.30 ng m−3 to 4.37 ng m−3. This study demonstrates the presence of inhalable fraction of nylon 66 MPs in the indoor environment and their mass concentrations were determined using HPLC-MS/MS. [ABSTRACT FROM AUTHOR]

Modulating the photogenerated electrons of CeO2 to activate O2 and efficiently photocatalytic degra- dation of chlorophenols is a highly desired goal. Herein, we have successfully fabricated an FePc/CeO2 heterojunction through H-bond induced assembly. The photocatalytic degradation of 2,4-DCP by the amount-optimized FePc/CeO2 nanocomposite was improved by 3 times compared with that by pure CeO2. By means of electron paramagnetic resonance (EPR) and single wavelength photocurrent spec- troscopy, it is confirmed that the excellent photocatalytic performance is mainly attributed to the for- mation of the Z-scheme heterojunction, which promotes charge separation and transfer, and the intro- duction of FePc broadens the visible light absorption range of the heterojunction. Moreover, O2 tempera- ture-programmed-desorbed curves and electrochemical O2 reduction measurement results demonstrate that the single Fe-N4(II) site in FePc is more conducive to promoting O2 activation than that of other metal phthalocyanines. Based on in situ FT-IR and liquid chromatography-tandem mass spectrometry (LC-MS/MS), a possible reaction pathway of 2,4-DCP degradation was proposed. This study provides a novel strategy for preparing CeO2 based Z-scheme heterojunctions with abundant monoatomic sites for pollutant degradation. [ABSTRACT FROM AUTHOR]

Introduction: Triple-negative breast cancer (TNBC) represents a significant global health crisis due to its resistance to conventional therapies and lack of specific molecular targets. This study explored the potential of Eriocephalus racemosus (E. racemosus) as an alternative treatment for TNBC. The cytotoxic properties and high-resolution respirometry mitochondrial activities of E. racemosus against the MDA-MB 231 TNBC cell line were evaluated. Methods: Hexane solvent and bioactive fraction extractions of E. racemosus were performed, while mass spectrometry-based metabolite profiling was used to identify the phytochemical constituents of the extracts. The extracts were further tested against MDA-MB 231 TNBC cells to determine their cytotoxicity. The mode of cell death was determined using flow cytometry. The activities of caspases 3, 8, and 9 were assessed using a multiplex activity assay kit. Glycolytic activity and High-resolution respirometry measurements of mitochondrial function in the MDA-MB 231 cell line were conducted using the Seahorse XFp and Oroboros O2K. Results: Metabolite profiling of E. racemosus plant crude extracts identified the presence of coumarins, flavonoids, sesquiterpenoids, triterpenoids, and unknown compounds. The extracts demonstrated promising cytotoxic activities, with a half maximal inhibitory concentration (IC50) of 12.84 µg/mL for the crude hexane extract and 15.49 µg/mL for the bioactive fraction. Further, the crude hexane and bioactive fraction extracts induced apoptosis in the MDA-MB-231 TNBC cells, like the reference drug cisplatin (17.44%, 17.26% and 20.25%, respectively) compared to untreated cells. Caspase 3 activities confirmed the induction of apoptosis in both cisplatin and the plant crude extracts, while caspase 8 and 9 activities confirmed the activation of both the intrinsic and extrinsic apoptosis pathways. Increased levels of glycolytic activity were observed in the hexane crude extract. High-resolution respiratory measurements showed elevated mitochondrial activities in all mitochondrial states except for complex-IV activity. Conclusion: These findings support further exploration of E. racemosus as a potential therapeutic agent for TNBC, offering a promising avenue for the development of targeted treatments with minimal adverse effects. [ABSTRACT FROM AUTHOR]

It is a consensus in the international manned space field that factors such as microgravity during the space flight can cause anxiety, depression and other important brain function abnormalities in astronauts. However, the neural mechanism at the molecular level is still unclear. Due to the limitations of research conditions, studies of biological changes in the primate brain have been comparatively few. We took advantage of -6° head-down bed rest (HDBR), one of the most implemented space analogues on the ground, to investigate the effects of simulated weightlessness on non-human primate brain metabolites. The Rhesus Macaque monkeys in the experiment were divided into three groups: the control group, the 42-day simulated weightlessness group with HDBR, and the recovery group, which had 28 days of free activity in the home cage after the HDBR. Liquid chromatography-mass spectrometry (LC-MS) was used to perform metabolomics analysis on specific brain areas of the monkeys under three experimental conditions. Our results show that simulated weightlessness can cause neurotransmitter imbalances, the amino acid and energy metabolism disorders, and hormone disturbances. But these metabolomics changes are reversible after recovery. Our study suggests that long-term brain damage in space flight might be reversible at the metabolic level. This lays a technical foundation for ensuring brain health and enhancing the brain function in future space studies. [ABSTRACT FROM AUTHOR]

This document provides concise summaries of several articles and research studies related to dermatology and contact allergies. The topics covered include non-compliance with nickel regulations, the association between atopic dermatitis and multimorbidity, contact sensitization to rubber additives, the long-term effectiveness of dupilumab treatment for atopic dermatitis, co-sensitizations and cross-reactivities to textile dyes, propolis sensitization and impurities, and various studies on contact allergies and patch testing. These studies offer valuable insights into the prevalence, causes, and treatment of dermatological conditions and contact allergies. [Extracted from the article]

Vitamin A plays a critical role in various biological functions, including vision, cellular differentiation, and immune regulation. However, accurately assessing its status, particularly in obese individuals, presents challenges due to potential alterations in metabolism and distribution. This study utilized Liquid Chromatography–Tandem Mass Spectrometry (LC–MS/MS) methodology to precisely measure serum vitamin A concentrations in population of UAE. The methodology's reliability and precision, as demonstrated through validation procedures, underscore its potential utility in clinical settings. Employing the Multiple Reaction Monitoring mode of positive ion electrospray ionization, the LC–MS/MS system achieves a limit of detection (LOD) of 0.48 ng/mL in serum, while adhering to FDA-US regulations for accuracy and compliance. A key aspect of this study was the application of LC–MS/MS to assess vitamin A status in an obese population within UAE. By employing a diverse cohort of 452 Emirati participants, including 277 individuals from a randomized controlled trial who were assessed at baseline and at 6th month, and 175 healthy individuals aged 18–82 assessed at baseline, this study explores the relationship between obesity and vitamin A levels, shedding light on potential implications for health and well-being. It was an observational study based on a new vitamin A method and participants were asked to eat vitamin A rich foods. The robust performance of the LC–MS/MS methodology positions it as a valuable tool for clinical research. By accurately quantifying vitamin A levels in human serum, this methodology opens avenues for advancing our understanding of vitamin A physiology and its implications for health, particularly in obese populations. In summary, this LC–MS/MS methodology presents a potent tool for clinical studies, providing reliable, specific, and robust detection of vitamin A in human serum, thus, opening a new frontier for advancing our understanding of vitamin A related physiology and health in the obese population. [ABSTRACT FROM AUTHOR]

A high‐fat diet (HFD) is one of the main causes of obesity and metabolic diseases. The liver is particularly affected by HFD causing metabolic dysfunction associated with fatty liver disease. Therefore, different strategies are used to mitigate the negative effects of HFD. This study aimed to assess the protective effects of walnut extract against HFD‐induced toxicity in mice. The mice were fed HFD and walnut extract alone or in combination. The walnut extract was analyzed for composition using high‐performance liquid chromatography with a diode array detector (HPLC‐DAD) and ultra‐high‐performance liquid chromatography with mass spectrometry (UHPLC–MS/MS). Serum lipid profile; liver histology; hepatic antioxidants such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px), lipid peroxidation (TBARS), and reduced glutathione (GSH); inflammatory markers like IL‐6 and TNF‐α; and phospholipids were determined. Results showed that phenolic acids, epicatechin, catechin, benzaldehyde, and juglone were the main constituents in the extract. The HFD group showed increased hepatic fat accumulation as evidenced by biochemical and histopathological examinations compared to the control animals. The HFD group mice also showed increased body and cardiac weights, modified lipid profiles, decreased antioxidant status, and increased levels of hepatic inflammatory markers. The weights of the body and heart, lipid profiles, antioxidant contents (CAT, SOD, GSH‐Px, TBARS, and GSH), and pro‐inflammatory cytokines (IL‐6 and TNF‐α) were all normalized by consuming walnut extract. Similarly, the HFD group had significantly high amounts of hepatic lipase, phospholipid, and lysophospholipid levels, which were improved by walnut extract. In conclusion, walnut extract has been shown to play a unique role in promoting the recovery of liver damage caused by a high‐fat diet. [ABSTRACT FROM AUTHOR]

This article presents an efficient one-step synthesis of tetrahydropyrazolo[1,5- a ]pyrimidines through the recyclization of N -arylitaconimides with aminopyrazoles. The heterocyclic system of pyrazolo[3,4- b ]pyrimidine is known for its diverse biological properties, making its derivatives significant in pharmaceutical and medicinal chemistry. The study focuses on the regio- and chemoselective cascade reaction of N -arylitaconimides with 5-aminopyrazoles, demonstrating a new approach to synthesizing pyrazolo[1,5- a ]pyrimidines and pyrazolo[3,4- b ]pyridines. The methodology, involving boiling in isopropyl alcohol with acetic acid, yields selectively either pyrazolo[3,4- b ]pyridines or pyrazolo[1,5- a ]pyrimidines based on the substituents in the aminopyrazoles. The study elucidates the reaction mechanism, structural characterization using NMR spectroscopy, and confirms the structures via high-performance liquid chromatography and mass spectrometry. The simplicity and synthetic potential of this approach make it a valuable method for the preparation of these heterocyclic frameworks. [ABSTRACT FROM AUTHOR]

Background: Podocyte injury is a common pathologic mechanism in diabetic kidney disease (DKD) and obesity-related glomerulopathy (ORG). Our previous study confirmed that Inonotus obliquus (IO) improved podocyte injury on DKD rats. The current study explored the pharmacological effects, related mechanisms and possible active components of IO on ORG mice. Methods: Firstly, by combining ultra-high performance liquid chromatography tandem mass spectrometry analysis (UPLC-Q-TOF-MS) with network pharmacology to construct the human protein-protein interaction mechanism and enrich the pathway, which led to discover the crucial mechanism of IO against ORG. Then, ORG mice were established by high-fat diet and biochemical assays, histopathology, and Western blot were used to explore the effects of IO on obesity and podocyte injury. Finally, network pharmacology-based findings were confirmed by immunohistochemistry. The compositions of IO absorbed in mice plasma were analyzed by UPLC-Q-TOF-MS and molecular docking was used to predict the possible active compounds. Results: The network pharmacology result suggested that IO alleviated the inflammatory response of ORG by modulating TNF signal. The 20-week in vivo experiment confirmed that IO improved glomerular hypertrophy, podocyte injury under electron microscopy, renal nephrin, synaptopodin, TNF-α and IL-6 expressions with Western blotting and immunohistochemical staining. Other indicators of ORG such as body weight, kidney weight, serum total cholesterol, liver triglyceride also improved by IO intervention. The components analysis showed that triterpenoids, including inoterpene F and trametenolic acid, might be the pharmacodynamic basis. Conclusion: The research based on UPLC-Q-TOF-MS analysis, network pharmacology and in vivo experiment suggested that the amelioration of IO on podocyte injury in ORG mice via its modulation on TNF signal. Triterpenoids were predicated as acting components. [ABSTRACT FROM AUTHOR]

Lenvatinib is a first-line therapy for the treatment of hepatocellular carcinoma (HCC), an active multi-target tyrosine kinase inhibitor (TKI). The interaction between Traditional Chinese Medicine (TCM) and chemicals has increasingly become a research hotspot. The objective of this study was to pinpoint the effects of three flavonoids on the metabolism of lenvatinib. Enzyme reaction system was established and optimized in vitro, and in vivo experiments were conducted in Sprague-Dawley (SD) rats, where the analytes were detected by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/ MS). We found that among three flavonoids, luteolin and myricetin had strong inhibitory effects on lenvatinib metabolism, with half-maximal inhibitory concentration (IC50) values of 11.36 ± 0.46 µM and 11.21 + 0.81 µM in rat liver microsomes (RLM), respectively, and 6.89 ± 0.43 µM and 12.32 + 1.21 µM in human liver microsomes (HLM), respectively. In Sprague-Dawley rats, the combined administration of lenvatinib and luteolin obviously expanded the exposure to lenvatinib; however, co-administered with myricetin did not have any changes, which may be due to the poor bioavailability of myricetin in vivo. Furthermore, the inhibitory type of luteolin on lenvatinib showed an un- competitive in RLM and a mixed in HLM. Collectively, flavonoids with liver protection, especially luteolin, may inhibit lenvatinib metabolism in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Voriconazole is a broad-spectrum triazole antifungal agent. A number of studies have revealed that the impact of C-reactive protein (CRP) on voriconazole pharmacokinetics was associated with the CYP2C19 phenotype. However, the combined effects of CYP2C19 genetic polymorphisms and inflammation on voriconazole pharmacokinetics have not been considered in previous population pharmacokinetic (PPK) studies, especially in the Chinese population. This study aimed to analyze the impact of inflammation on the pharmacokinetics of voriconazole in patients with different CYP2C19 genotypes and optimize the dosage of administration. Data were obtained retrospectively from adult patients aged ≥16 years who received voriconazole for invasive fungal infections from October 2020 to June 2023. Plasma voriconazole levels were measured via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). CYP2C19 genotyping was performed using the fluorescence in situ hybridization method. A PPK model was developed using the nonlinear mixed-effect model (NONMEM). The final model was validated using bootstrap, visual predictive check (VPC), and normalized prediction distribution error (NPDE). The Monte Carlo simulation was applied to evaluate and optimize the dosing regimens. A total of 232 voriconazole steady-state trough concentrations from 167 patients were included. A one-compartment model with first order and elimination adequately described the data. The typical clearance (CL) and the volume of distribution (V) of voriconazole were 3.83 L/h and 134 L, respectively. The bioavailability was 96.5%. Covariate analysis indicated that the CL of voriconazole was substantially influenced by age, albumin, gender, CRP, and CYP2C19 genetic variations. The V of voriconazole was significantly associated with body weight. An increase in the CRP concentration significantly decreased voriconazole CL in patients with the CYP2C19 normal metabolizer (NM) and intermediate metabolizer (IM), but it had no significant effect on patients with the CYP2C19 poor metabolizer (PM). The Monte Carlo simulation based on CRP levels indicated that patients with high CRP concentrations required a decreased dose to attain the therapeutic trough concentration and avoid adverse drug reactions in NM and IM patients. These results indicate that CRP affects the pharmacokinetics of voriconazole and is associated with the CYP2C19 phenotype. Clinicians dosing voriconazole should consider the patient’s CRP level, especially in CYP2C19 NMs and IMs. [ABSTRACT FROM AUTHOR]

Background: Xiaojin Pill (XJP) is a traditional Chinese medicine prescribed for treating benign prostatic hyperplasia (BPH). It has been proven to have multiple effects, such as regulating sex hormone levels, exhibiting anti-tumor, anti-inflammatory, analgesic, and anti-platelet aggregation properties, and improving immunity. However, the material basis of XJP's therapeutic effect on BPH and its metabolic process in vivo remains to be clarified. At the same time, many microorganisms that exist in the urogenital tract, including those related to BPH, can also affect the health of the host. Methods: Using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), the chemical components of XJP were identified. A BPH model was created through bilateral testicular ablation and injections of testosterone propionate. A comprehensive evaluation of XJP efficacy was conducted using pathological ELISA, TUNEL, and immunohistochemical techniques. In addition, UPLC-MS metabolomics and 16S rRNA sequencing revealed the serum metabolic profile and intestinal microbiota composition. We performed a Spearman correlation coefficient analysis to highlight the interactions between "intestinal microbiota-serum factors" and "intestinal microbiota-metabolites." Results: XJP contains 91 compounds that alleviate pathologies of BPH in rats, decreasing prostate weight, index, and serum levels of Dihydrotestosterone (DHT), Prostate-Specific Antigen (PSA), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) levels. It inhibits prostatic epithelial cell apoptosis and downregulates Bax, TGF-β1, and IGF-1 proteins in the caspase-3 pathway. Metabolomics studies have revealed 10 upregulated and 10 downregulated metabolites in treated rats, with 5-methylcytosine, uracil, and cytosine enriched in pyrimidine metabolism. L-arginine plays a pivotal role in metabolic pathways encompassing pyrimidine metabolism, arginine biosynthesis, and the mammalian target of rapamycin (mTOR) signaling pathway. 16S rRNA sequencing revealed that XJP optimized the diversity and balance of intestinal flora in BPH rats by decreasing the Bacteroidetes/Firmicutes (B/F) ratio, enhancing the beneficial bacteria, such as Eggerthellaceae, Anaerovoracaceae, and Romboutsia, and suppressing the dysfunctional bacteria, such as Atopobiaceae, Prevotellaceae_NK3B31_group, Dorea, and Frisingicoccus. According to the Spearman correlation coefficient analysis, Lactobacillus was found to be most associated with serum factors, whereas Romboutsia showed the highest correlation with metabolites. This finding suggests that XJP modulates pyrimidine metabolism disorders in BPH rats, a regulation that aligns closely with Romboutsia, Prevotellaceae_NK3B31_group, Lactobacillus, Chujaibacter, and Enterorhabdus, thereby providing valuable biological insights. Conclusion: In summary, these findings indicate that XJP possesses a synergistic anti-BHP effect through its multi-component, multi-target, multi-gut microbiota, and multi-metabolic pathway properties. The effect involves the regulation of sex hormone levels, growth factors, and the anti-epithelial cell apoptosis process. The modulation of specific gut microbiota by the host and the involvement of multiple metabolic pathways are likely one of the significant mechanisms of XJP in treating BPH. Notably, pyrimidine metabolism and the intestinal microbial ecosystem are closely intertwined in this process. [ABSTRACT FROM AUTHOR]

Background: Multiple sclerosis (MS) is a demyelinating disease of the central nervous system characterized by increased inflammation and immune responses, oxidative injury, mitochondrial dysfunction, and iron dyshomeostasis leading to demyelination and axonal damage. In MS, incomplete remyelination results in chronically demyelinated axons and degeneration coinciding with disability. This suggests a failure in the ability to remyelinate in MS, however, the precise underlying mechanisms remain unclear. We aimed to identify proteins whose expression was altered in chronic inactive white matter lesions and periplaque white matter in MS tissue to reveal potential pathophysiological mechanisms. Methods: Laser capture microdissection coupled to proteomics was used to interrogate spatially altered changes in formalin-fixed paraffin-embedded brain tissue from three chronic MS individuals and three controls with no apparent neurological complications. Histopathological maps guided the capture of inactive lesions, periplaque white matter, and cortex from chronic MS individuals along with corresponding white matter and cortex from control tissue. Label free quantitation by liquid chromatography tandem mass spectrometry was used to discover differentially expressed proteins between the various brain regions. Results: In addition to confirming loss of several myelin-associated proteins known to be affected in MS, proteomics analysis of chronic inactive MS lesions revealed alterations in myelin assembly, metabolism, and cytoskeletal organization. The top altered proteins in MS inactive lesions compared to control white matter consisted of PPP1R14A, ERMN, SIRT2, CARNS1, and MBLAC2. Conclusion: Our findings highlight proteome changes in chronic inactive MS white matter lesions and periplaque white matter, which may be crucial for proper myelinogenesis, bioenergetics, focal adhesions, and cellular function. This study highlights the importance and feasibility of spatial approaches such as laser capture microdissection-based proteomics analysis of pathologically distinct regions of MS brain tissue. Identification of spatially resolved changes in the proteome of MS brain tissue should aid in the understanding of pathophysiological mechanisms and the development of novel therapies. [ABSTRACT FROM AUTHOR]

Background: Head and neck paragangliomas (HNPGLs) are rare neuroendocrine tumors that pose significant challenges in both diagnosis and treatment. The pathogenic mechanism remains unclear, and there is no proteomic analysis-based molecular classification. Therefore, gaining a deeper understanding of this disease from the protein level is crucial because proteins play a fundamental role in the occurrence and development of tumors. Methods: We collected 44 tumor samples from patients diagnosed with HNPGL. The adrenal paraganglioma tissue (N = 46) was used as the disease control group and the chorda tympani nerves (N = 18) were used as the control group. High-pH reversed-phase liquid chromatography and liquid chromatography with tandem mass spectrometry analyses were used to build an integrated protein database of tumor samples. We then obtained two sets of differentially expressed proteins between the tumor group and the control group to identify the unique proteomic signatures of HNPGLs. Ingenuity pathway analysis annotations were used to perform the functional analysis. Subsequently, we developed a clinically relevant molecular classification for HNPGLs that connected the clinical characteristics with meaningful proteins and pathways to explain the varied clinical manifestations. Results: We identified 6,640 proteins in the HNPGL group, and 314 differentially expressed proteins unique to HNPGL were discovered via inter-group comparison. We identified two HNPGL subgroups that significantly differed in clinical manifestation and proteomic characteristics. On the basis of the proteomic results, we proposed a pathogenic mechanism underlying HNPGL. Conclusion: We conducted a comprehensive analysis of the molecular mechanisms of HNPGL to build, for the first time, a clinically relevant molecular classification. By focusing on differential proteomic analyses between different types of paragangliomas, we were able to obtain a comprehensive description of the proteomic characteristics of HNPGL, which will be valuable for the search for significant biomarkers as a new treatment method for HNPGL. [ABSTRACT FROM AUTHOR]

Introduction: Epididymal lumen fluids provides a stable microenvironment for sperm maturation. Ca2+ binding protein CABS1 is known to maintain structural integrity of mouse sperm flagella during epididymal transit of sperm. Besides, CABS1 was reported to contain anti-inflammatory peptide sequences and be present in both human saliva and plasma. However, little is known about the role of CABS1 in regulation of the microenvironment of epididymal lumen fluids.Methods: To further confirm the role of CABS1 in epididymis, we identified the expression of CABS1 in epididymal lumen fluids. Moreover, high performance liquid chromatography, coupled with tandem mass spectrometry technique was used to analyze the metabolic profiles and in vivo microperfusion of the cauda epididymis and inductively coupled plasma mass spectrometry (ICP-MS) assays was used to detect the concentration of metal ion of mouse cauda epididymal lumen fluids in CABS1 deficient and normal mice.Results: The results showed that CABS1 is present in epididymal lumen fluids, and the concentration of calcium in epididymal lumen fluids is not changed in Cabs1-/- male mice. Among 34 differential metabolites identified in cauda epididymis, 21 were significantly upregulated while 13 were significantly downregulated in KO cauda epididymis. Pathway analysis identified pyrimidine metabolism, inositol phosphate metabolism, arachidonic acid metabolism, purine metabolism and histidine metabolism as relevant pathways in cauda epididymis.Discussion: The perturbations of mitochondrial dysfunction and inflammation may be the crucial reason for the poor performance of Cabs1-/- sperm. [ABSTRACT FROM AUTHOR]

Consumers are increasingly looking for healthier and sustainable diets. Plant-based diets rich in legumes satisfy this demand. Legumes contain protein, dietary fibers and starch. Technological processes can separate these fractions, which can be used as supplements, or as ingredients. Nonetheless, legumes are susceptible to fungal infection, causing a potential health concern, since some fungi can produce mycotoxins: toxic secondary metabolites. The aim of this work was to analyze the fate of mycotoxins during different stages of the production process of legume derived products from the raw materials to final products. An extraction followed by liquid chromatography-tandem mass spectrometry was used for the analysis, revealing the presence of enniatin B (ENN B), alternariol monomethyl ether (AME), deoxynivalenol, T2-toxin, nivalenol, fumonisin B1 and sterigmatocystin in raw materials, intermediate products and side streams. The alkaline solubilization steps, were effective in reducing ENN B; however, AME was found in one of the final products. [ABSTRACT FROM AUTHOR]

OBJECTIVE To establish pilot data on the plasma concentrations of SC amikacin at 2 doses in red-eared sliders and evaluate concurrent plasma biochemistry parameters. ANIMALS 8 adult red-eared sliders (Trachemys scripta elegans). METHODS Amikacin was administered SC at target doses of 5 and 10 mg/kg with a 3-week washout period. Blood samples were collected at 0, 24, 48, 72, and 96 hours postadministration. Plasma amikacin concentrations were quantified using liquid chromatography tandem mass spectrometry. Plasma biochemistry analyses were performed before amikacin administration, 1 week post 5-mg/kg administration, and 1 week post 10-mg/kg administration. RESULTS Mean maximum amikacin plasma concentrations were recorded 24 hours after 5-mg/kg and 10-mg/kg dosing and were 17.5 ± 2.32 µg/mL and 23.6 ± 2.92 µg/mL, respectively. Mean plasma concentrations after 5-mg/kg dosing steadily decreased to 9.1 ± 0.92 µg/mL by 96 hours postadministration. Amikacin remained detectable in all plasma samples 3 weeks post 5-mg/kg dosing with a mean plasma concentration of 1.04 ± 0.22 µg/mL. Mean plasma concentrations after 10-mg/kg dosing did not decrease over the 96-hour study period. There were no clinically relevant changes in biochemistry parameters. CLINICAL RELEVANCE Amikacin persists at detectable plasma levels for at least 3 weeks after SC administration of a 5-mg/kg dose in redeared sliders, which has not previously been reported in any species. No biochemistry changes consistent with renal toxicity occurred after either dose. Use caution with repeated amikacin dosing in this species until further studies can better characterize cumulative amikacin pharmacokinetics and toxic threshold. [ABSTRACT FROM AUTHOR]

Context: The contamination of feedstuffs with multi-mycotoxins and their transfer to milk is an important concern because it can affect the health of both animals and humans. Aims: This study determined the nutrient composition and quantified the mycotoxins present in dairy feedstuffs and in cow's milk. Methods: Samples of feedstuffs and milk were collected from 11 dairy farms in northern Tunisia for physicochemical composition and mycotoxin analyses. The extraction of mycotoxins was performed by the QuEChERS procedure and the presence of 26 mycotoxins was checked using liquid or gas chromatography with tandem mass spectrometry (LC–MS/MS and GC–MS/MS). Key results: Nutrient contents differ among feedstuffs (P < 0.05). The pH values of oat, ryegrass and pulp silages varied from 4.6 to 5.3. Dry-matter (DM) content was highest for concentrate feeds and hay (90% and 86% DM respectively). Crude protein (CP) content was highest in concentrate feeds (15.8% DM). The neutral detergent fibre, acid detergent fibre and acid detergent lignin contents were highest in green grass, hay, and silage. Eight Fusarium mycotoxins, enniatins (ENA1, ENB, ENB1), beauvericine (BEA), HT-2 toxin (HT-2), deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON), Fumonisin B2 (FB2) and one Alternaria mycotoxin tentoxin (TENT) were detected at low concentrations. There was a significant (P < 0.05) difference in the levels of contamination by ENB between the samples of forages and concentrate feeds. The ENs (ENA1, ENB, ENB1) were the most frequently detected combination of mycotoxins. Milk analysis for fat, CP, lactose and dehydrated dry extract averaged 3.49%, 3.10%, 4.71%, and 8.77% respectively; urea concentration was of 34.01 mg/dL, milk pH was 6.5, and a somatic cell count of 1168.63 103 cells/mL was found. Most milk samples (82%) were contaminated with ENB. Conclusions: The levels of mycotoxin contamination in feedstuffs and milk were low and do not present a risk for dairy cattle and consumer health. Implications: Mycotoxins in feedstuffs and milk should be regularly analysed to make sure that quality and safety standards are met. The safety and nutritional quality of milk for human consumption depends on the quality of the feed sources consumed by dairy cattle. Our study has shown that mycotoxins, harmful toxins, detected in some feed sources (e.g. forage silages, hay and concentrates) could be transferred to milk. Strategies for efficient management of feed sources should be developed and the transferability of mycotoxins to milk should be controlled to ensure that the food supply chain is safe and free from harmful toxins. [ABSTRACT FROM AUTHOR]

Background: Gap junction remodeling is an important cause of ventricular arrhythmia in heart failure. However, it remains unclear whether renal denervation (RDN) regulates gap junction remodeling in heart failure. To explore the effect of RDN on gap junction remodeling in dogs with high-pacing-induced heart failure. Methods: Fifteen dogs were randomly divided into control (n=5), heart failure (HF) (n=5), and RDN+HF (n=5) group. A high-pacing-induced-heart failure model was established using rapid right ventricular pacing for 4 weeks. The RDN+HF group underwent surgical and chemical ablation of both renal arteries before 4 weeks rapid right ventricular pacing. After 4 weeks, echocardiography, High-Performance Liquid Chromatography-Mass Spectrometry test for norepinephrine and epinephrine, and pathological analysis were performed in the above 3 groups. Further, immunohistochemical staining was used to detect tyrosine hydroxylase, ChaT, connexin 43 (Cx43), and connexin 40 (Cx40). Connexin 43 and Cx40 expression was detected by western blotting. Transmission electron microscopy was used to observe the gap junction. Results: Compared to the control group, myocardial fibrosis and sympathetic hyperactivity were observed in the HF group. Immunohistochemical staining and western blotting showed that Cx40 expression and Cx43 expression was significantly reduced in the HF group. Compared with the HF group, the RDN+HF group showed reduced sympathetic hyperactivity, Cx40 expression, Cx40/Cx43 ratio, and increased Cx43 expression. Conclusion: Renal denervation alleviates gap junction remodeling in high-pacinginduced heart failure dogs. [ABSTRACT FROM AUTHOR]

Objectives Temocillin, a carbapenem-sparing β-lactam antibiotic, is commonly used at the standard 4 g/day dosage for treating complicated urinary tract infections (cUTIs). However, pharmacokinetic/pharmacodynamic (PK/PD) data supporting this regimen is limited. This study evaluated the plasma pharmacokinetics (PK) and PTA of temocillin in non-critically ill cUTI patients with varying degrees of renal insufficiency (RI). Methods In this single-centre clinical study, 22 cUTI patients received a fixed 4 g/day (2 g q12h, intravenously) temocillin dose, irrespective of renal function (no RI: n  = 5, mild RI: n  = 8, moderate RI: n  = 9). Plasma samples were collected post-dosing for LC-MS analysis of total and unbound temocillin levels. Monte Carlo simulations were performed based on the established PK/PD target of ≥35% f T > MIC (minimal inhibitory concentration). Results Among patients, the highest plasma drug exposure and PK/PD target attainment were observed in those with moderate RI (median AUC0–12h = 1143 h.mg/L and % f T > MIC = 68%), followed by mild RI patients (median AUC0–12h = 918 h.mg/L and % f T > MIC = 34%), and the lowest in those with healthy kidney function (median AUC0–12h = 692 h.mg/L and % f T > MIC = 26%). Simulations indicated that the 4 g/day temocillin dose achieves 90% PTA only for glomerular filtration rate < 60 mL/min and MIC ≤ 8 mg/L. Conclusion The standard temocillin dose may need to be increased from 4 to 6 g/day to treat non-critically ill cUTI patients, in line with recent EUCAST recommendations. For patients with moderate RI, who experience higher exposure due to reduced renal drug clearance, 4 g/day temocillin remains appropriate. [ABSTRACT FROM AUTHOR]

A variety of LSD analogs have emerged in recent years with dual purposes of avoiding prosecution from possession while providing new options for those willing to experiment with hallucinogenic drugs. In this study, a previously published automated sample preparation method for LSD and its primary metabolite (OH‐LSD) was utilized to extract LSD, OH‐LSD, and nine LSD analogs from urine. The liquid chromatography tandem mass spectrometry (LC–MS/MS) method was modified from the previously published LC conditions to utilize a different analytical column and gradient elution program. Mobile phases of 10 mM ammonium formate with 0.1% formic acid in deionized water (mobile phase A) and 0.1% formic acid in methanol (mobile phase B) were employed. The method was validated to ANSI/ASB Standard 036 with a 0.1 ng/mL limit of detection for all analytes and was utilized for the analysis of 325 urine specimens. Although no LSD analogs were observed in the samples analyzed, this validated method was demonstrated to be suitable for the analysis of these compounds in laboratories seeking to expand their testing scope. Automated sample preparation allows for the efficient analysis of these analytically challenging compounds with minimal manual handling. Additionally, there was no increased analytical time burden when the LC column and gradient were modified to target nine additional analytes. Detection may improve as new reference standards are developed to allow laboratories to focus on the metabolic products of these analogs. For now, this validated procedure can assist with the routine analysis and surveillance of these emerging substances. [ABSTRACT FROM AUTHOR]

Vitamin K is one of the many health-promoting substances whose impact on the human body has been underestimated until recently. However, recently published research results have changed this situation, prompting some researchers to consider it a new panacea for diseases of old age. The result is a significant increase in interest in the accurate analysis of vitamin K in various types of samples, ranging from food, through dietary supplements, to biological matrices and clinical trials, both observational and interventional. This review summarizes the current state of knowledge about the proven and speculated biological activity of vitamin K and its importance for the world's aging societies, including the methods used for its isolation and analysis in various matrices types. Of all the analytical methods, the currently preferred methods of choice for the direct analysis of vitamin K are chromatographic methods, in particular liquid chromatography-tandem mass spectrometry. This technique, despite its sensitivity and selectivity, requires an appropriate stage of sample preparation. As there is still room for improvement in the efficiency of these methods, especially at the sample preparation stage, this review shows the directions that need to be taken to make these methods faster, more efficient and more environmentally friendly. [ABSTRACT FROM AUTHOR]

In order to understand the status of aflatoxin contamination in dried chilli products in Gansu Province and the risk of dietary exposure, a total of 106 samples of dried chilli products from farmers’ markets and supermarkets in 14 prefecture-cities of Gansu Province were collected and analysed by isotope dilution liquid chromatography-tandem mass spectrometry. The results showed that the detection rate of aflatoxin in dried chilli products in Gansu Province was 30.2%, and the average level was 1.57 μg/kg. The detection rates of dried chillies, paprika, and chilli powders were 16.7%, 43.6%, and 46.2%, respectively. The detection rates of aflatoxin in dried chilli products from shops and farmers’ markets were 22.5% and 40.0%, respectively. The dietary exposure of AFB1 was 0.0001 μg/kg bw/day, and the MOE calculated from its average concentration was 305. [ABSTRACT FROM AUTHOR]

In 1998, Health Canada mandated folic acid fortification of white flour and enriched grain products to prevent neural tube defects. At the time, neither the Canadian Nutrient File (CNF) nor product labels reflected the actual folate content of foods. We aimed to assess if 20 years post-fortification, the CNF values for total folate and synthetic folic acid accurately reflect amounts determined by direct analysis. Using the 2001 Food Expenditure Survey and ACNielsen Company data, we identified 10–15 of the most purchased fortified foods across seven food categories in Canada. Total folate concentrations were determined by tri-enzyme digestion and microbial assay. Folic acid concentrations were determined using liquid chromatography-tandem mass spectrometry. Except for "cooked pastas", mean total folate content of foods (n = 89) were significantly higher than CNF values across categories (p < 0.05), reflecting 167% ± 54% of CNF values. Similarly, mean folic acid content of foods was higher than CNF values for all categories except "cooked pastas" (p < 0.05), with a mean of 188% ± 94% of CNF values; the latter CNF values included uncooked pasta. In sum, 20 years post-fortification, and 10 years since the last direct measurement, CNF and product label values still underestimate actual total folate and the folic acid content of foods. These findings emphasize that dietary estimates established using the CNF may significantly underestimate actual intakes and thus caution should be exercised when interpreting estimates of nutritional adequacy based on these values. [ABSTRACT FROM AUTHOR]

Purpose: Routine therapeutic drug monitoring of apixaban is currently not recommended but may however be warranted in some situations and for some patient groups to provide better and safer treatment. Due to limited data on apixaban concentrations in different subpopulations, it is still unclear which group of patients could possibly gain from monitoring. The purpose of this study was to examine apixaban exposure in patients with obesity compared with normal-weight patients. Methods: Forty patients with obesity (mean BMI 39.4 kg/m2) and 40 controls with normal weight (mean BMI 23.4 kg/m2), treated with apixaban 5 mg twice daily were included. The patients were matched for age, sex, and renal function. Trough and peak apixaban concentrations were measured with LC‒MS/MS methodology. Results: The median trough concentrations in patients with obesity (58.7, range 10.7–200.7 ng/ml) were slightly higher than those in patients with normal weight (52.0, range 31.0–150.9 ng/ml) (p < 0.05). Notably, the variability in trough concentration was considerably higher in patients with obesity. Peak concentrations were similar in both groups, with a median of 124.5 ng/ml (range 82.0–277.5) and 113.5 ng/ml (range 75.5–334.6) in patients with obesity and normal weight, respectively. Conclusion: Apixaban exposure did not vary substantially between obese and normal weight matched controls, implying that general dose adjustments are not required. However, vast interindividual variability was observed in patients with obesity, suggesting that measuring the concentrations could be valuable for specific patients. Further research is needed to identify which specific patients may benefit from this approach. [ABSTRACT FROM AUTHOR]

Background: 6‐Nitrodopamine (6‐ND) is a novel endogenous catecholamine that has a potent relaxant action on vascular smooth muscle in vitro. Objectives: To evaluate the basal release of 6‐ND and noradrenaline from rabbit‐isolated corpus cavernosum (RbCC) and its relaxing action on this tissue. Methods: Rabbit corpus cavernosa were dissected and suspended in a 5‐mL organ bath containing oxygenated Krebs‐Henseleit's solution. 6‐ND and noradrenaline release was quantified by liquid chromatography coupled to tandem mass spectrometry. The relaxant activity of 6‐ND was assessed in RbCC strips pre‐contracted with endothelin‐1 (10 nM). Results: Rabbit corpus cavernosum presented basal release of both 6‐ND (2.9 ± 0.8 ng/mL, n = 12) and noradrenaline (1.7 ± 1.3 ng/mL, n = 12). The 6‐ND release was reduced by pre‐treatment with Nω‐nitro‐l‐arginine methyl ester (l‐NAME) (100 µM), whereas that of noradrenaline was unaffected. Tetrodotoxin (TTX, 1 µM) abolished the noradrenaline release but had no effect on 6‐ND release, indicating a non‐neurogenic origin for 6‐ND. 6‐ND and the selective dopamine D2‐agonist L‐741,626 caused concentration‐dependent RbCC relaxations (pEC50 of 11 ± 0.15 and 11.15 ± 0.28, respectively). Pre‐treatment with either l‐NAME or the soluble guanylate cyclase inhibitor 1H‐[1,2,4] oxadiazolo[4,3‐a]quinoxalin‐1‐on (ODQ) (100 µM) caused a rightward shift of the concentration–response curve to 6‐ND, without affecting the L‐741,626 responses. In TTX (100 nM)‐pre‐treated preparations, neither l‐NAME nor ODQ shifted the 6‐ND concentration–response curve. Dopamine, noradrenaline, and adrenaline caused concentration‐dependent RbCC contractions. Pre‐incubation with 6‐ND concentration‐dependently inhibited the dopamine‐induced contractions, without affecting those induced by either noradrenaline or adrenaline. Discussion and conclusion: 6‐Nitrodopamine is the most potent endogenous relaxant agent in RbCC ever described and represents a novel mechanism by which NO causes corpus cavernosum smooth muscle relaxation. The finding that 6‐ND acts as a truly selective dopamine D2‐receptor antagonist indicates that the balance of dopamine and 6‐ND release/synthesis may be the main mechanism that modulates corpus cavernosum smooth muscle tonus in vivo. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Ruminant milk composition can be affected by many factors, primarily interspecies differences, but also environmental factors (e.g., season, feeding system, and feed composition). Pasture-based feeding systems are known to be influenced by seasonal effects on grass composition. Spring pasture is rich in protein and low in fiber compared with late-season pasture, potentially inducing variability in the composition of some milk metabolites across the season. This study aimed to investigate interspecies and seasonal differences in the milk metabolome across the 3 major commercial ruminant milk species from factories in New Zealand: bovine, caprine, and ovine milk. Samples of bovine (n = 41) and caprine (n = 44) raw milk were collected monthly for a period of 9 mo (August 2016–April 2017), and ovine milk samples (n = 20) were collected for a period of 5 mo (August 2016–January 2017). Milk samples were subjected to biphasic extraction, and untargeted metabolite profiling was performed using 2 separate liquid chromatography high-resolution mass spectrometry analytical methods (polar metabolites and lipids). Major differences in the milk metabolome were observed between the 3 ruminant species, with 414 of 587 (71%) polar metabolite features and 210 of 233 (87%) lipid features being significantly different between species. Significant seasonal trends were observed in the polar metabolite fraction for bovine, caprine, and ovine milk (17, 24, and 32 metabolites, respectively), suggesting that the polar metabolite relative intensities of ovine and caprine milk were more susceptible to changes within seasons than bovine milk. We found no significant seasonal difference for the triglycerides (TG) species measured in bovine milk, whereas 3 and 52 TG species changed in caprine and ovine milk, respectively, across the seasons. In addition, 4 phosphatidylcholines and 2 phosphatidylethanolamines varied in caprine milk within the season, and 8 diglycerides varied in ovine milk. The interspecies and seasonal metabolite differences reported here provide a knowledge base of components potentially linked to milk physiochemical properties, and potential health benefits of New Zealand pasture-fed dairy ingredients. [ABSTRACT FROM AUTHOR]

Aim: To analyse the association between serum bile acid (BA) profile and heart failure (HF) with preserved ejection fraction (HFpEF) in patients with metabolic dysfunction‐associated fatty liver disease (MAFLD). Methods: We enrolled 163 individuals with biopsy‐proven MAFLD undergoing transthoracic echocardiography for any indication. HFpEF was defined as left ventricular ejection fraction >50% with at least one echocardiographic feature of HF (left ventricular diastolic dysfunction, abnormal left atrial size) and at least one HF sign or symptom. Serum levels of 38 BAs were analysed using ultra‐performance liquid chromatography coupled with tandem mass spectrometry. Results: Among the 163 patients enrolled (mean age 47.0 ± 12.8 years, 39.3% female), 52 (31.9%) and 43 (26.4%) met the HFpEF and pre‐HFpEF criteria, and 38 serum BAs were detected. Serum ursodeoxycholic acid (UDCA) and hyocholic acid (HCA) species were lower in patients with HFpEF and achieved statistical significance after correction for multiple comparisons. Furthermore, decreases in glycoursodeoxycholic acid and tauroursodeoxycholic acid were associated with HF status. Conclusions: In this exploratory study, specific UDCA and HCA species were associated with HFpEF status in adults with biopsy‐confirmed MAFLD. [ABSTRACT FROM AUTHOR]

Sperm after short-term storage in vitro is widely used for artificial fertilization in aquaculture. It has been shown that short-term storage affects sperm motility characteristics, resulting in diminished fertility. However, the detrimental effects of short-term sperm storage on embryos development have remained unexplored in single-base methylome resolution. The main aim of the present study was to investigate DNA methylation in the offspring of common carp (Cyprinus carpio) derived from short-term stored sperm. Sperm were stored in artificial seminal plasma on ice (0–2 °C) for 0, 3 and 6 days in vitro, fertilization was performed using oocytes from a single female, and embryos were collected at the mid-blastula stage. In the DNA methylation study, DNA from both sperm and embryos was extracted and analysed using liquid chromatography with tandem mass spectrometry (LC–MS/MS). Concurrently, DNA methylation levels of embryos in single base were evaluated through whole genome bisulfite sequencing (WGBS). Sperm storage showed negative effects on sperm motility, viability, and DNA integrity, but had no effect on global DNA methylation of spermatozoa and resulting embryos. Results from the WGBS showed that methylation of 3313 differentially methylated regions (DMRs)-target genes was affected in the embryos fertilized with the 6-day-stored sperm, and the identified DMRs were mainly involved in cell adhesion, calcium, mitogen-activated protein kinase and adrenergic signalling, melanogenesis, metabolism and RNA transport. Such results suggest that prolongation of storage time may have certain impacts on embryonic development. These initial results provide valuable information for future consideration of the DNA methylome in embryos generated from short-term stored sperm, which are used for genetic management of broodstock in aquaculture. [ABSTRACT FROM AUTHOR]

Radiation-induced intestinal injury (RIII) commonly occur during abdominal-pelvic cancer radiation therapy; however, no effective prophylactic or therapeutic agents are available to manage RIII currently. This study aimed to clarify the potential of probiotic consortium supplementation in alleviating RIII. Male C57BL/6J mice were orally administered a probiotic mixture comprising Bifidobacterium longum BL21, Lactobacillus paracasei LC86, and Lactobacillus plantarum Lp90 for 30 days before exposure to 13 Gy of whole abdominal irradiation. The survival rates, clinical scores, and histologic changes in the intestines of mice were assessed. The impacts of probiotic consortium treatment on intestinal stem cell proliferation, differentiation, and epithelial barrier function; oxidative stress; and inflammatory cytokines were evaluated. A comprehensive examination of the gut microbiota composition was conducted through 16S rRNA sequencing, while changes in metabolites were identified using liquid chromatography-mass spectrometry. The probiotic consortium alleviated RIII, as reflected by increased survival rates, improved clinical scores, and mitigated mucosal injury. The probiotic consortium treatment exhibited enhanced therapeutic effects at the histologic level compared with individual probiotic strains, although there was no corresponding improvement in survival rates and colon length. Moreover, the probiotic consortium stimulated intestinal stem cell proliferation and differentiation, enhanced the integrity of the intestinal epithelial barrier, and regulated redox imbalance and inflammatory responses in irradiated mice. Notably, the treatment induced a restructuring of the gut microbiota composition, particularly enriching short-chain fatty acid-producing bacteria. Metabolomic analysis revealed distinctive metabolic changes associated with the probiotic consortium, including elevated levels of anti-inflammatory and antiradiation metabolites. The probiotic consortium attenuated RIII by modulating the gut microbiota and metabolites, improving inflammatory symptoms, and regulating oxidative stress. These findings provide new insights into the maintenance of intestinal health with probiotic consortium supplementation and will facilitate the development of probiotic-based therapeutic strategies for RIII in clinical practice. [ABSTRACT FROM AUTHOR]

The scientific literature contains little reliable data regarding new psychoactive substances and designer drugs, making it difficult to assess toxic blood levels and potentially lethal threshold. Here, we report a fatal co-intoxication involving two uncommon drugs ‒ alpha-methyltryptamine (AMT) and 5-(2-methylaminopropyl)-benzofuran (5-MAPB) ‒ combined with exposure to benzodiazepines, ephedrine, and norephedrine. AMT and 5-MAPB were quantified using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC/MS-MS), revealing concentrations of AMT 4690 ng/mL and 5-MAPB 101 ng/mL in postmortem peripheral blood. We additionally reviewed the literature to help interpret the likely roles of these molecules in the occurrence of death. [ABSTRACT FROM AUTHOR]

This study aimed to develop and validate a multi-mycotoxin analysis method applied to cashew nuts by employing a miniaturized QuEChERS method followed by determination by ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). Satisfactory recoveries for the concentrations 1, 10 and 30 ng g−1, ranging from 66% (fumonisin B1) to 110% (ochratoxin A) and relative standard deviations lower than 9% (fumonisin B2) were obtained for the target compounds. Limits of quantification ranged from 0.004 ng g−1 (sterigmatocystin) to 0.59 ng g−1 (alternariol). The applicability of the analytical method was verified by analyzing 30 cashew nut samples from the city of Rio de Janeiro, RJ, southeastern Brazil. Aflatoxins M1, G2, G1, B2, B1, ochratoxin A and sterigmatocystin were detected, respectively, in 27%, 10%, 17%, 30%, 30%, 30% and 50% of the analyzed samples, at maximum concentrations of 0.56, 0.67, 1.43, 2.02, 4.93, 4.81, and 0.35 ng g−1. The maximum limit established by Brazilian legislation for aflatoxins was not exceeded by any of the analyzed samples. [ABSTRACT FROM AUTHOR]

Bakery products, including biscuits, cakes and breads, generally present a high content of simple sugars of rapid absorption, high fat content and low amount of dietary fiber, which make them highly caloric foods. Although sucrose is a very important ingredient in bakery products for its preservation characteristics and a significant source of energy, there is a growing interest in replacing this sugar with alternative substances, such as high-intensity sweeteners (HIS) that provide sweetness with no or low calories. In Brazil, there is no data on the use of HIS in this class of food. Therefore, the objective of this study was to evaluate the presence of HIS in baked food commercially available in the country and estimate the dietary exposure to these food additives. For that, an analytical method was established for the simultaneous determination of nine HIS in bakery products using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS). Sample preparation steps were required based on mechanical kneading for homogenization, hexane extraction of fats, dilution in mobile phase and vortex homogenization, prior to injection into the system. The results obtained during validation showed that coefficients of variation (CV%) for precision were lower than 13.8% and the accuracy was between 91.6% and 109.1%. Aspartame, acesulfame potassium, sodium cyclamate, saccharin, sucralose and steviol glycosides were found in the samples, used alone or in combinations of up five substances. Steviol glycosides were the most found HIS in biscuit samples, while sucralose was the most common sweetener in cake and bread samples. Analysis of product labels revealed only three different claims,.i.e. 'no sugar', 'no added sugar' and 'zero sugar', with the latter being found in 70% of the samples. Exposure to HIS through the consumption of bakery products estimated per eating occasion showed no concerns regarding toxicological risk. [ABSTRACT FROM AUTHOR]

To explore potential factors contributing to high fluoroquinolone resistance levels, it is essential to develop analytical methods capable of detecting residues and trace amounts of antibiotic use in broilers. The aim of the present study was to develop and in-house validate a sensitive UHPLC-MS/MS method capable of determining enrofloxacin (ENR) and flumequine (FLU) residues at slaughter age (day 45) when the animals were treated with these antimicrobials one day after hatching. Residue depletion of ENR and FLU in feathers was also assessed. Two experimental trials were performed, both consisting of 5 different treatment groups. In the first trial animals were treated with ENR and in the second one with FLU. The developed method was successfully validated and was found to be sensitive enough to detect residues of fluoroquinolones in the feathers up until slaughter age in all treatment groups. Average ENR concentration on day 45 was 10 ng g−1 feather after drinking water treatment, with all concentrations above the limit of quantification (LOQ) of 5 ng g−1 feather. For FLU average concentration on day 45 after drinking water administration was 4 ng g−1 feather, with an LOQ of 1 ng g−1 feather. Therefore, the method is suited for application to monitor fluoroquinolone use in broilers. [ABSTRACT FROM AUTHOR]

The methanol extract of Inula viscosa (IVM) was investigated for its antioxidant potential using the DPPH and ABTS radical scavenging as well as iron chelating assays (ICA). The total phenol (TPC) and flavonoid contents (TFC) of IVM were determined using the Folin-Ciocalteu and aluminum trichloride methods, respectively. Antimicrobial activity of different concentrations of I. viscosa methanol extract was investigated by disc diffusion and broth microdilution method. The IVM extract was found to be containing TPC (236.78 ± 7.63 mg GAE/g) and TFC (94.36 ± 1.86 mg QE/g). Antioxidant activity IC50 values for the DPPH, ABTS and ICA assays were found to be 277.7 ± 3.68, 2.44 ± 0.02, and 222.1 ± 0.71 µg/mL, respectively. The MIC values of the IVM on the tested microorganisms ranged from 0.48 to 7.81 mg/mL. Furthermore, IVM extract was demonstrated 18.32 ± 1.37%, 23.06 ± 1.05%, 4.72 ± 0.13%, 15.13 ± 0.37% and 37.64 ± 4.02% inhibition against tyrosinase, α-amylase, α-glucosidase, AChE and BChE, respectively. In the results of LC-MS/MS analysis, acacetin, quercetin, chlorogenic acid and protocatechuic acid were determined as most dominant compounds. These findings suggested that this plant may be a natural resource for creating novel medicinal compounds. [ABSTRACT FROM AUTHOR]